July 28, 2015

Since the anomaly of prominent ears is uncommon in India, our international editor Mr. ACH Watson had suggested that I approach Mr. K.J. Stewart, a senior plastic surgeon from Scotland to supply information on the subject. He in turn asked his senior core trainee Ms. C.J. Stewart to write up the material which has been vetted by him and is reproduced below as sent by them.

Introduction

The correction of prominent or “bat” ears (apostasis otis) is a continual challenge for the plastic surgeon. With over 200 techniques described for the correction of this deformity, there is no single widely used procedure that has been adopted by most surgeons. A successful operation can significantly improve a patient’s quality of life, and is also highly rewarding for the surgeon. However, patients must be motivated and selected carefully, with realistic expectations of surgery (Table 1).

In this text, we shall review the basic principles of several common operative techniques. An understanding of auricular anatomy and embryology is essential for accurate diagnosis and surgical treatment (See Chapter 41: Congenital Abnormalities of the Ear).

Initial Assessment

The selection of an operative technique must be tailored to the individual pathology of the prominent ear, associated anatomical features (figure 1) and quality of auricular cartilage. In most patients, ear prominence relates to a combination of issues; most commonly underdevelopment of the anthelix and anterior conchal rotation related to inadequate tethering to the mastoid. Two less common reasons are an excessively deep conchal bowl, and rarely obtuse inferior crus. Surgery should be directed at correcting these exact issues identified on clinical examination.

Desired outcomes of otoplasty are to reduce the cephaloauricular angle to 15-20° and emphasise the antihelices fold without the interruption of contour. A simple method of anthropometric assessment is to measure the perpendicular distance from the mastoid to helical rim most projected at the Frankfort line; a line drawn connecting the infraorbital rim and the superior aspect of the external auditory meatus (figure 2). The aesthetic ideal for this distance lies between 17-22mm; beyond this one slips into the ill-defined area of prominence. When measured pre and post-operatively, this distance is used to give an accurate estimate of medialisation. Numerous further anthropometric criteria for a properly shaped auricle have been suggested by various authors (Table 2).

Additional surgical fixation or conchal reduction may be required to treat protruding lobules and/or conchal hypertrophy respectively. Unfortunately conchal hypertrophy is often over diagnosed, and conchal reduction over-performed. Since post-operative complications can often result in severe auricular deformities, each ear should be analysed individually regarding the problem areas, and the surgical approach that causes the least injury to the cartilage should be used.

Contributing features that accentuate auricular protrusion are prominence of the mastoid process, protrusion of the lower auricular pole (cauda helicis, lobule and cavum concha) or a prominent tipped auricular pole. It is important to elicit auricular malposition or asymmetry, facial asymmetry, chronic otitis, diminished auditory acuity or decreased facial musculature that may indicate a more complex auricular deformity or syndromic pattern requiring special preparation or contraindicating surgery.

Surgical Techniques

Anterior Cartilage Scoring

This method of otoplasty first described by Chongchet involves weakening of the anterior auricular cartilage by making multiple partial thickness incisions or “scoring” in order to restore the normal curvature of the anthelical fold and soften the external contour of the corrected prominent ear (figure 3). This can be performed under local or general anaesthesia, but preferably the latter with most patients being young children.

The ear is folded back to create an anti-helical fold which is marked with ink. After liberal infiltration with bupivucaine with one in hundred thousand saline-adrenaline solution, both in front and back of the ear, an elliptical excision of skin, mid-way between the helical border and cephaloauricular angle, is made along the whole length of the ear on its cranial surface. A needle is introduced from the front of the ear over the area already marked for the anti-helix and passed through the whole thickness of the ear. When the needle’s point appears on the cranial surface, it is dipped in marking ink and withdrawn so as to tattoo the cartilage. Several such points are marked along the length of the ear by repeating the same procedure. The cartilage of the scapha is incised within the helical rim preserving at least 6mm of helical rim to maintain structural integrity. The anterior surface of the ear is degloved of its skin and multiple superficial curved scores are made in the cartilage along the proposed anti-helix to break the outer layer of the cartilage. The cartilage folds by virtue of these parallel but superiority diverging cuts. The incision in the scapha is repaired to the helical rim with a running PDS. The skin is closed and the area is dressed with soft cotton wool and covered with a firm bandage. (Chongchet, 1963).

Mustardé first described a technique in 1963 for creating an anthelical fold by utilising permanent conchoscaphal mattress sutures. The basis of this technique is the pliability of auricular cartilage when stripped of all the muscle and connective tissue that tends to hold it in a predetermined shape. Since that time, many subtle refinements of this method have been made, but fundamentals of the procedure remain unchanged.

Horlock, Misra and Gault described the concept of a posterior suturing with a posterior fascial flap (figure 4). Under general anaesthesia, a posterior auricular skin incision is made 8-10 mm behind and parallel to the helical rim. The skin above the cartilage is mobilised medially up to the mastoid and laterally to the helical rim. In order to prevent postoperative skin distortions, the mobilisation should not be extended beyond the helical rim. A composite flap of postauricular superficial musculoaponeurotic system (SMAS) and perichondrium is then raised by making an incision through the underlying fascial layer and perichondrium to the scaphoid cartilage. The flap is reflected posteriorly with care not to score the cartilage, and dissection continued posteriorly to the mastoid periosteum creating a pocket of adequate size to house the conchal bowl.

Conchoscaphoid and conchomastoid sutures are then inserted using a round bodied needle and braided polyester permanent material (Ethibond) to create the new anthelical fold, starting caudally. The round-bodied needle avoids the tendency of the suture material to cut through the delicate cartilage. To facilitate access to the mastoid pocket, all sutures are held with a clip and tied only when the desired ear shape is achieved. The posterior fascial flap is then replaced over the cartilage and sutured to the helical rim with 5/0 vicryl rapide to cover all ethibond sutures, and overlying skin closed with 4/0 prolene subcuticular sutures that are removed at one week postoperatively. A standard head bandage is worn until the removal of sutures, after which a headband worn at night for six weeks.

Compared to anterior scoring and posterior suturing without a fascial flap, long term results of this technique demonstrate the lowest clinical recurrence rate (4.8%) and the best cosmetic result (Schaverien MV et al, 2008). In a ten-year single-centre study of 81 unilateral otoplasty patients, early complications were significantly more common in cartilage-scoring and posterior-suturing techniques than posterior suturing in combination with a fascial flap; highly beneficial for younger patients in whom short-term complications are less well tolerated. (Szychta P, Stewart KJ, 2013). For these reasons, and for its versatility and adjustability, this technique has become our treatment of choice for prominent ear correction in children.

Further correction of the overall position of the auricle is most commonly performed by conchal rotation in combination with anthelix sutures. The posterior aspect of cartilage is accessed through a retroauricular incision made parallel to the helical rim and prepared in a caudal direction up to the mastoid plane. Excessive retroauricular connective, fatty, and muscular tissue is excised, completely sparing the temporal fascia. Subsequently, the auricle is rotated dorsally and fixed between the conchal cartilage and the dorsal mastoid periosteum, using mattress sutures. (Furnas, 1968)

Less commonly, conchal reduction is required to reduce the height or size of deep conchal bowls. To estimate the degree of conchal hypertrophy, the finger is placed on the antihelix and the ear set back to its aesthetically pleasing position. The relevant crescent chondrocutaneous portion of the ear is excised, leaving less cartilage and more skin to ensure tension free closure. (Converse, 1955) The concha is sutured with one row of 4/0 Ethibond sutures and is pre-placed to avoid interference with the rest of the operation. Prior to skin closure, these retention sutures are tightened and the auricle is fixed in the desired position.

Ear Reduction

Deformities of the auricle can be corrected by a variety of subtle refinement techniques. Helical prominences, such as superior outer helical rim cartilage excess (i.e “Spock” ears) can be corrected using the modified Anterior-Buch technique. This elegant procedure aesthetically produces a more rounded helical rim using two chondrocutaneous advancement flaps that extend onto scapha and anthelix:

The auricular skin and cartilage are incised along the helical crease from the root of the helix into the lobe. A crescent-shaped section of anterolateral scaphal skin and cartilage is excised from the defect to helical root sulcus, followed by a Burow’s triangle of the anterolateral skin excised from the lobe. Full thickness step cuts are carefully measured and excised from the ends of the helical rim flaps to exactly interlock when advanced together. The posteromedial auricular skin is dissected completely from the auricular cartilage to the auriculocephalic sulcus. The helical rim flaps are advanced together under no tension with meticulous cartilage apposition and skin eversion using vertical mattress sutures. This facilitates good aesthetic results, with minimal alteration of ear contour and slight reduction of vertical height. (Butler, 2003)

Lobuloplasty can be performed by marking out the desired ear lobe size, infiltrating with local anaesthetic, and then making an anterior and posterior curvilinear fusiform incision to excise a V-shaped, wedge of excess lobule. The skin is closed with permanent suture (e.g. 6/0 nylon) and sutures removed on the sixth postoperative day. No pressure dressing is required.

Thickened Ears

Gentle thinning of auricular cartilage is most commonly performed using an anterior approach; whereby an incision is made in the anterior aspect of the helical rim and a skin flap reflected towards the meatus, revealing anterior cartilage. A special diamond rasp or cooled dental burr is used to recreate scaphoid and triangular fossae, smooth the anthelix and thin the conchal bowl until the preferred C-shaped curvature is attained (Raunig, 2005)

Thick auricular cartilage with low elasticity can be shaped using the Weerda technique, whereby a diamond drill is used to weaken the auricular cartilage immediately above and below the intended new anthelical fold and anthelical crus through retroauricular access (figure 5). Continuous rinsing during drilling is important to prevent heat-induced chondronecrosis. To fix the antihelix in the intended position, full-thickness mattress sutures of slowly absorbable or non-absorbable suture material are placed at the positions with the corresponding markings. The use of non-absorbable suture material minimises the risk of recurrence.

Indications for secondary surgery include recurrent prominence, under-correction, and distortion of scaphoid fossa, distortion of anthelical fold, hypertrophic conchal bowl and an over-corrected mid-portion; the so- called “telephone ear.” Such deformities can be addressed by a variety of surgical techniques including posterior suturing, conchal bowl reduction, reconstruction with conchal cartilage and reconstruction with cost al cartilage (figure 8).

Careful exploration of the patient’s concerns and aspirations pre-operatively is pivotal to achieving a successful outcome, with close evaluation of their motivations for secondary surgery evaluated against a realistic assessment of surgical probabilities. The complexity of proposed surgery should be balanced against the patient’s tolerance of secondary donor sites, length of surgery and secondary scarring. For example, the patient may misperceive a telephone ear deformity as under-corrected upper and lower poles. After careful risk assessment and exploration of surgical options, they may prefer a simple procedure to bring the upper and lower poles into planar harmony, rather than undergo a complex reconstructive procedure with additional scarring.

This assessment also helps to identify early evidence of body dysmorphic disorder in those young people with irrational body dissatisfaction requesting secondary otoplasty. Warning features may include unjustified criticism of previous surgeons, lack of social support and dysfunctional interpersonal relationships. Virtually without exception, these patients are poor candidates for further intervention.

For recurrent prominence or planar disharmony between the upper, middle or lower poles of the ear, posterior cartilage suturing with a fascial flap (Horlock, Misra and Gault) can facilitates further set back and contouring. Under local anaesthesia infiltration, the previous posterior scar is incised or excised, and skin dissected in the subdermal plane to the scaphoid cartilage. The composite SMAS flap is raised and any previous interfering suture material removed. Sutures are reinserted to adjust areas where there is either contour deficiency or inadequate rotation. Conchoscaphoid and conchomastoid sutures are placed to augment the anthelical fold and conchal bowl respectively using 4/0 ethibond on a round bodied needle, and tied with varying tension to create a progressively more obtuse anthelical fold in the upper pole. The fascial flap is re-positioned to cover these sutures, secured with 5/0 vicryl rapide and overlying skin closed. Dressings and sutures are retained for one week post-operatively.

Conchal reduction with posterior suturing is an effective technique for recurrent prominence in the context of pre-existent but unrecognized conchal hypertrophy or stiffened cartilage (See Conchal Surgery).

Disruption of the structural integrity of the ear within a limited area is an indication for conchal cartilage graft reconstruction. Via a posterior-auricular approach, a conchal cartilage graft is harvested from the contralateral (or occasionally ipsilateral) ear. The relevant area of cartilage is then exposed using an anterior or posterior approach, and any contour distortions shaved, providing a smooth surface for the positioning of the conchal graft that is secured with 5/0 non-absorbable sutures.

Major deformity of the ear cartilage requires more complex reconstruction with autologous costal cartilage. This may be performed in one or two stages:

Stage 1: Cartilage is firstly harvested from the chest by making a transverse incision to expose fascia of the rectus abdominis and the external oblique muscle. Dissection between the two muscles and undermining of the perichondrium facilitates exposure of the cartilage that is harvested using a Doyen raspatory, inserted beneath the cartilage at the costochondral junction. The harvested cartilage is carved and thinned into constructs to replace the anatomical defects, and remaining parts of cartilage cut into 2mm blocks. The perichondrium is closed with an absorbable suture blocks inserted into the reconstructed cavity with the help of a funnel. A drain is left behind the muscular layer, and overlying muscle, muscular fascia and skin closed. The recipient site is prepared after incision, usually by posterior approach with careful degloving of the deformed auricular cartilage. 5/0 non-absorbable sutures are places to secure the new construct to overlapping auricular cartilage, and drain applied. The postauricular skin is then closed.

Stage 2: Total ear reconstruction for cartilage atrophy with infection or an insufficient skin envelope may require an additional operation to abduct the ear from the skull. Six months post operatively the skin is incised posteriorly and a small skin graft harvested and secured.

Conclusion

Otoplasty remains a challenging operation for the plastic surgeon, where knowledge of suitable surgical techniques and the correct performance of the otoplasty procedures are crucial for a good cosmetic result. This review has covered several proven techniques of otoplasty, with emphasis on a tailored anatomical analysis of the individual prominent ear to select the most effective procedure that will minimise injury to auricular cartilage. Careful exploration of the patient’s concerns and aspirations are also pivotal in achieving a successful outcome.